This invention relates generally to the operation of vehicles, and more specifically, to controlling the operation of railroad locomotives.
Modern freight trains can be over a mile long and can include many cars and locomotives. More specifically, such trains typically include more than one locomotive to provide the necessary pulling power and stopping tractive effort. The additional locomotives may be grouped at the head of the train or can appear at locations distributed along the length of the train that are remote from the lead locomotive. Locomotives are coordinated by cable-based communication when co-located at the head of the train or via radio-linked communications when the locomotives are distributed along the length of the train. Distributed configurations simplify slack handling among freight cars and air brake operations, facilitate reducing fuel consumption in large trains, and facilitate reducing inter-freight car forces around curves.
The manner in which train engineers drive a multi-locomotive plus freight train consist has a direct effect on the efficiency of fuel use and maintenance of safe train integrity. Engineers are trained extensively and tend to operate similar routes from day to day, but have limited information to help make decisions that impact performance during a trip. Based on their past experience with specific locomotives, track grade, weather conditions and the current freight load, drivers adjust throttle and brake settings to maintain speed below posted or dispatcher changed track limits, to arrive at the next destination (to pass a train or move into a siding to allow oncoming traffic passage) at a prescribed time, while simultaneously assuring dynamic slack action among freight cars is minimized.
The engineer and central dispatcher work collaboratively to keep the train on schedule, but each may lack crucial details of the other""s environment which would benefit the railroad overall in terms of operations efficiency (throughput of trains) or fuel usage. For example, the train driver may know neither the fuel-efficiency/speed relationship for his train nor the actual slack in required arrival time at the next destination, and so travels at track speed limits using excess fuel. By displaying valid, current information about system and train performance attributes, the driver has an opportunity to make tradeoffs in speed vs. arrival time that minimize fuel use and arrive at the required schedule time.
In one aspect, a method for pacing a vehicle along a path of travel is described. The method includes determining a geographical location of the vehicle, displaying a vehicle position icon representative of the geographical location, determining an optimal position for the vehicle, displaying a pace icon representative of the optimal position for the vehicle, and operating the vehicle to maintain a vehicle position icon displayed on the operator pace display substantially coincident with the pace icon displayed on the operator pace display.
In another aspect, a system for pacing a vehicle along a path of travel is described. The system includes at least one on-board tracking system configured to determine a geographical location of the vehicle, at least one on-board computer configured to determine a display position of a pace icon, and at least one on-board operator pace display configured to display the pace icon at a position determined by the on-board computer, the operator pace display further configured to display the vehicle position, as determined by the on-board computer, relative to the pace icon.
In yet another aspect, a locomotive pacing system for pacing a locomotive along a path of travel is provided. The locomotive pacing system includes at least one tracking system configured to determine a geographical location of the locomotive, at least one on-board computer, including a memory and a non-volatile storage medium in communication with the at least one tracking system. The on-board computer is configured to determine a display position of a pace icon. The system also includes at least one operator pace display in communication with the at least one on-board computer wherein the operator pace display is configured to display the pace icon at a position determined by at least one of the on-board computer and a central computer, and the operator pace display further configured to display the locomotive position, as determined by at least one of the on-board computer and a central computer, relative to the pace icon. The pacing system includes a system for monitoring locomotive operation including sensors configured to determine at least one of locomotive speed, engine power, train slack, track curvature, track incline locomotive heading and heading rate wherein heading represents the direction of travel of the locomotive, reverser handle position, tracklines 8 and 9, online/isolate switch position, fuel remaining, and an interface coupled to the sensors and in communication with the on-board computer.